I have mixed feelings on Pocahontas, but I think the recent backlash is mainly due to social media and Native Americans being more vocal about their opposition to the film, as well as the Internet making more people aware of the tragic life of the historical Pocahontas/Matoaka.
I think when the movie came out historians and Native Americans were largely unhappy with it, but there were some who appreciated the representation. Conservatives largely didn't like it because they thought it was too "politically correct" and didn't like that non-Christian spirituality was so heavily featured. But a lot of moderate or liberal people thought it was a fairly progressive film compared to the previous stereotypes of Native Americans depicted. Nowadays, I think a lot of the people that would have championed it as progressive in the 90s would now view the movie as problematic.
I think now more people have done more research on the actual historical figure of Pocahontas and the whitewashed Disney version feels insensitive. Pocahontas was a little girl when she met John Smith. Most historians believe Smith made up the story about her saving him. She was at one point taken captive by colonizers and many Native Americans believe she was raped. Some oral tradition from Native Americans claim Kocoum was her first husband, who was killed by colonists after Pocahontas's capture (this is subject to debate and not verified). After her marriage to John Rolfe, her conversion to Christianity was likely forced, and she had to take on the Christian name of Rebecca. She was paraded around in England as an example of a civilized/tamed savage. She died in her early 20s before she could ever return home to America.
With all of this in mind, many people find it distasteful that a young woman who had her identity stripped away from her by colonists and died tragically young is now the focus of a Disney film where she's aged up, highly sexualized and put in a romance with a colonizer. The movie also perpetuates many stereotypes about Native Americans, such as them being these noble mystical beings that are so in tune with nature that they can summon spirits, talk to trees and steal bear cubs away from their mom. The song "Savages" has also been criticized for having a "see both sides are bad" framing, when history has taught us that the colonizers did way more harm to Native Americans than vice versa, and Native Americans shouldn't be portrayed as being in the wrong for wanting to defend their land from invaders.
I think the movie Pocahontas meant well and attempted to send a message about the dangers of hatred, but they definitely missed the mark in the execution. It may have been better if the movie was an entirely ficitonal story. I know the name "Pocahontas" has a lot of historical recognition, but it also came with a lot of baggage that a G-rated Disney film wasn't equipped to handle.